Presentation can be fairly important. If you offer your homebrew to a friend, and they receive a cloudy drink with sediment floating around, their first impression of your work is not likely to be very positive. No matter what it tastes like, if it looks gross, that initial judgement is going to taint their overall opinion. The clarity of your mead is one of the first noticeable attributes of your drink; second only to it’s color. So, from an aesthetic standpoint, it’s important.
Mead can finish fermenting, and be in a drinkable state in a couple of weeks, especially at low alcohol levels. If the flavors in your mead don’t require much aging, then the next largest time sink is waiting for your mead to clear. They yeast, and any particles from your flavor additives or honey are all floating around in suspension after the vigorous churning they went through in the fermentation process. As the yeast slow down, they begin to fall out of suspension and sink to the bottom. With no more CO2 being produced, and creating an upward force, this settling process begins to speed up. Sometimes, however, things just don’t seem to want to drop. This tends to happen with especially fine particles quite a bit. With time, these stuck particles will eventually drop, but if you’re impatient or low on time, we’ll tackle a few methods to help clear your mead.
Cold Crashing
The most basic method is cold crashing. If the yeast have just recently finished eating all the sugar in your must, they may still be actively moving around and not quite willing to drop. A quick drop in temperature will force them to enter a less active state, somewhat like a hibernation. This can help in getting the clearing started.
Racking
Siphoning your mead into another container can help degas your mead. That combined with getting everything all mixed up can also help to accelerate the clearing process. On occasion these simple methods are enough to get things moving, but there are some more advanced techniques if these fail.
Filtering
The most effective method to clear your mead is to filter it. A filtration system is one of the more expensive pieces of equipment you can buy, but is also the fastest, and most reliable way to remove the haze from your creation. Depending upon the size of the filter pads you get for your device, it can even serve double duty and remove any still living yeast from the drink. This allows you to back sweeten with impunity, with no worry of fermentation starting back up again. Effectively stabilizing it. You can read more about filtering in this article.
Fining Agents
Last but not least, there are fining agents. These are additives that can be added to your brew to help the particles within them to drop. There are a few different types, which work in different ways, but they all have some effect on the floating particles’ ability to stay buoyant within the liquid. Most of these particles have a small electric charge. Some of these fining agents make use of an opposing charged particle, often heavier than the one it is trying to attract, to attract those that are floating. These heavier particles will drop through your mead and pull the suspended ones towards them to the bottom. Beer tends to have a set group of popular additives so it can be pretty easy to know which fining agent works best to clear out your beer. Mead, however, seems to have a much broader array of additives being used in them, so it can take some trial and error to see which fining agent works the best. It won’t help much if your suspended particles are positively charged and you use a positively charged fining agent.
Another large group of fining agents rely on the process of absorption. These don’t carry a charge, but instead have a way of catching onto floating particles and binding with them as they fall down. There are also a few enzymes that can break down certain proteins which are known to cause haze.
Bentonite
Bentonite is a type of volcanic clay that happens to hold a negative charge. This means it should attract most of the positively charged particles in your mead. This clay also has the ability absorb a great deal of water, which causes it to expand to nearly 20 times its original size. So once it has bonded with the suspended material, it will swell up and sink.
Bentonite is especially interesting, because it can be added pre-fermentation. Most fining agents will only work after the fact. But if hydrated properly with hot water separately from the mead and added as a slurry, it can be added to the must. It will still settle to the ground, but fermentation will cause CO2 bubbles to form and lift the bentonite back to the top. The bentonite is pulling positively charge particles in its wake the whole time. These bubbles reach the surface and pop, and everything it was holding up will drop back to the bottom, pulling more positively charged particles with it. This elevator ride repeats through the fermentation, clearing it as it goes.
Some mead makers have found that this bouncing process can help temper the active yeast, as well. It keeps the fermentation from becoming too vigorous and ensures it moves at a more controlled pace. This can be good for reducing the fusel alcohols that warrant aging out to remove the heat or bite that young beverages are known for.
If you add bentonite post fermentation, it will only get the initial sinking to pull any particles with it. Unless you give it some outside help. If you degass your mead a few times a day after adding it, the released CO2 can drag the bentonite back up to the top.
Chitosan
Not exactly a fining agent, as it doesn’t act to clear currently suspended particles. Many fruits used in wine and mead contain both tartaric acid and potassium. These eventually react with one another to form potassium bitartrate. This appears as a clear, tasteless crystal like material. It is often referred to as “cream of tartar”, “tartrate crystals”, or “white diamonds”. These often appear after bottling, and while they are harmless, are another type of sediment that you might like to avoid.This is composed of chitin, which makes up the exoskeletons of crabs, shrimp and other shellfish. It is a positively charged particle, so will work on different types of suspended material than the bentonite will. Chitosan is very popular to use to clear white wines, as it does not require help from tannin to be effective (like gelatin does). It is often sold as part of a two pack with Kieselsol (a negatively charged particle), as the second step of Super Kleer – to be used a few days after A. Chitosan is known to be fairly gentle towards the character of a finished wine. It should not affect much other than the clearing you wish it to do.
Egg Whites
Probably one of the first fining agents ever used, egg whites hold a positive charge. Commonly used to clear red wines during barrel aging, egg whites also have a reputation for softening astringency and mellowing out the wine with no real negative effects. Preparing a whole egg to use as a fining agent takes a few steps, but this is a tried and true method dating back centuries. One egg is enough to clarify over 6 gallons. The whites should be separated and added to salted water. This will allow help it become more soluble. 1 egg, 0.1 liter of water, and 0.15g of salt is the suggested ratio. Whip it all together, and remove any foam, for this will float uselessly on top of your mead. It should be racked off the egg whites within 2 weeks. Powdered egg whites will also work, and may be preferred to avoid bacteria.
Gelatin
Gelatin is a positively charged particle that comes from an animal protein. Similar to bentonite, it can also be added pre-fermentation. Positively charged fining agents are recommended for Red wines, as they can help to remove excess tannins (negatively charged). It can be used in whites (or lighter colored meads without much tannin), but excessive gelatin can create a haze of its own. To avoid stripping too much from whites, it can be used with kieselsol (negative charge). This will act as a substitute for the lack of tannin and pull out the excess gelatin in your mead. Working together, they can reduce astringency and collect both types of charged particles that may be suspended.
Gelatin has a limited shelf life, being an animal product. So keep this in mind when purchasing. It comes in both powdered and liquid form. The powdered form is easier to regulate the necessary dosage.
Isinglass
Isinglass is a positively charged protein made from collagen, which is extracted from the swim bladders of fish. It is known for its gentle touch, and is not recommended for removing any heavy hazing in your mead. Isinglass will not strip out any flavor or character from your beverage like some of the other fining agents can. Often, it is used as a secondary fining agent to add the finishing touches to a drink after another agent is used. It produces a very thin layer of fine sediment. It comes in both liquid and powder forms.
Kieselsol
Also referred to as silicon dioxide, kieselsol is a negatively charged particle. Often paired with other fining agents of the opposite charge because it acts similar to tannin. This is also sold as the first step of the 2 part Super Kleer packs.
Casein/Potassium Caseinate
Casein is a milk protein. Similar to gelatin, it can be used to reduce tannin, and remove brown the brown tint that can occur with oxidation. Do not overuse, however, as it can strip out the character and colors you may wish to keep in your beverage. Casein can be difficult to use, as it will react with any acids in your mead (and honey can be fairly acidic). This reaction causes it to lose its effectiveness as a fining agent, if you try to simply stir it in. It is much more effective if it is injected into the mead via a baster or syringe, as the pressure keeps this reaction at bay.
Pectic Enzyme/Pectinase
Pectic enzyme is great for anything with a fruit additive. Fruits often have pectin, a long carbohydrate chain that does not like to settle out, and has some mild gelling properties. It tends to create a significant haziness in drinks if not dealt with. The pectin molecule is also quite large and can prove to be problematic for filtration, as it will gum up the filters. This enzyme helps to break it down so it can sink easier. Since this acts on the molecules themselves, it can be added pre-fermentation with no issues.
PVPP (Poly vinyl poly pyrrolidone)
PVPP is a synthetic polymer that will not dissolve in water. This means it cannot break down in your drink or leave any off-flavors behind. This is more of a tannin reducer than a strict fining agent. It can be used in place of gelatin, and will similarly remove oxidative odors and colors, as it removes the part of the enzyme in fruit that reacts with oxygen.
Often used alongside carbon to remove off-flavors, or with bentonite to produce a more compact sediment layer.
Sparkalloid
A popular brand of fining agent that is made from the fossilized remains of hard shelled algae. It comes in a powder in hot mix, or cold mix varieties. Hot mix is for wines or meads, cold for juices. It has quite a good reputation for making nice clear drinks without stripping out the character. It is mixed with hot water and then added to your mead. However, this is a slower acting fining agent that is suggested to use a whole month prior to bottling.
Carbon
While this is not strictly a fining agent, it is worth noting. Carbon can be used to remove odd odors from your mead. It is commonly used in things like air filtration units, and a similar principle applies to beverages. It can also remove off colors from your drink. Be careful not to overuse it, however. Carbon will strip out color, scent, and even flavor if you use too much of it, and could even develop its own off-flavor.
Metatartaric Acid
Not exactly a fining agent, as it doesn’t act to clear currently suspended particles. Many fruits used in wine and mead contain both tartaric acid and potassium. These eventually react with one another to form potassium bitartrate. This appears as a clear, tasteless crystal like material. It is often referred to as “cream of tartar”, “tartrate crystals”, or “white diamonds”. These often appear after bottling, and while they are harmless, are another type of sediment that you might like to avoid.